Tel Aviv University 
Dear all,
This week at the Horowitz seminar on Probability, Ergodic Theory and
Dynamical Systems at Tel Aviv University we are happy to have:
Speaker: Elon Lindenstrauss, Hebrew University
Title: Orbit closures for some higher rank Abelian actions
Date: Monday, March 28
Time: 14:30
Place: Schreiber 309
In 1967 Furstenberg discovered that any x2, x3 closed invariant subset of
R/Z is closed or finite, contrasting with the situation for sets
invariant under a single endomorphism. Even earlier, Cassels and
Swinnerton-Dyer have made a deep conjecture on products of linear forms
that is equivalent to a rigidity statement about orbit closures of the
diagonal group in SL(n,R)/SL(n,Z) (namely that they are compact iff the
orbit is periodic). However, the exact classification of orbit closures
can be quite tricky, even on the conjectural level. I will present some
positive and negative results in this direction based mostly on joint
works with U. Shapira and Z. Wang.
You may also be interested in the colloquium talk by Greg Kuperberg given
two hours before, from 12:15-13:15 on "What is quantum probability?", see
Best regards,

Seminar webpage:
Technion Math Net-2 (TECHMATH2)
Editor: Michael Cwikel   <> 
Announcement from: Ron Peled   <>